Tank for storage and delivery of fluids including functional components disposed on the tank wall

ABSTRACT

A tank for motor vehicle includes a tank wall, a fill opening, an outlet opening, a plurality of functional components, and a plurality of attachment formations. The tank wall forms an outermost casing of the tank. The fill opening passes through the tank wall for inlet of operating fluid into the tank. The outlet opening passes through the tank wall for outlet of the operating fluid. The plurality of functional components are designed for pumping and/or for cleaning and/or for detecting a property and/or for changing a property of the operating fluid. The plurality of attachment formations are designed as being integral with the tank wall for positioning of a plurality of functional components on the tank wall. The functional components are disposed on segments of the tank wall, which are arranged at an incline to each other.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims priority to German Application No. 10 2015 217763.7, filed Sep. 16, 2015. The entirety of the disclosure of theabove-referenced application is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a tank for motor vehicle operatingfluid for receiving a fluid, in particular an aqueous urea solution,comprising:

-   -   A tank wall forming an outermost casing of the tank, with an        inner side adjacent to the tank interior and an outer side        adjacent to the external environment of the tank,    -   A fill opening passing through the tank wall for the filling of        the operating fluid into the tank,    -   An outlet opening passing through the tank wall for outlet of        the operating fluid from the tank,    -   A plurality of functional components, wherein the functional        components are configured for pumping and/or for cleaning and/or        for detection of a property and/or for changing a property of        the operating fluid, and    -   A plurality of attachment formations formed integral with the        tank wall for arranging a plurality of functional components on        the tank wall.

DESCRIPTION OF THE RELATED ART

A tank of this type for motor vehicle operating fluid is known from EP 2029 865 B1. An attachment plate or base plate which covers a tankopening at the bottom of the tank is disposed on the interior side ofthis tank. The base plate is a part of the outermost casing of the tankand thus forms a part of the tank wall. The base plate includes anoutlet opening through which the operating fluid can flow. In addition,at least one functional component is disposed on the base plate.Furthermore, the base plate can include a cavity so that the wallsegments of the base plate divide the tank interior into a plurality ofpartial volumes, wherein the at least one functional component can bedisposed inside this cavity. According to the teaching of EP 2 029 865B1, the number of assembly steps needed for attachment of functionalcomponents to the tank wall can be reduced by all functional componentsbeing disposed on the base plate. Consequently, the assembly of thefunctional components is completed in that the base plate plus allfunctional components disposed on the base plate are attached to thetank wall as a pre-mounted subassembly of functional components.However, the simplified assembly of a tank known from EP 2 029 865 B1 isaccompanied by a loss of design flexibility.

SUMMARY OF THE INVENTION

Usually the base plates or pre-mounted subassemblies of functionalcomponents known from the prior art are attached to a pre-definedattachment formation of the tank. However, due to space constraints inthe motor vehicle, it is not always possible to dispose the pre-mountedsubassembly of functional components at the pre-defined attachmentformation on the tank.

In addition, to perform their function of pumping and/or cleaning and/ordetecting a property and/or changing a property of the operating fluidin a satisfactory manner, functional components of this kind (such as acapacitive fill level sensor or a capacitive quality sensor)—whichrequire a differing orientation from each other due to their physicaloperating principle and usage—must be arranged on the base plate suchthat when the base plate is mounted to the tank, they will be disposedin a pre-defined orientation relative to the expected surface level ofthe operating fluid occurring in the tank interior. If the base plate isdesigned as a flat wall component, then the possibility to arrange theindividual functional components in mutually different orientations islimited. This the situation can indeed be remedied in that the baseplate is produced with mutually inclined assembly segments on which theindividual functional components can be arranged in mutually differentorientations. But then the complexity and consequently the cost of abase plate increases accordingly. In addition, these assembly segmentsare frequently located entirely inside the interior of the tank. Due tothe limited surface area of the base plate, there can also be mutualinterference among the individual functional components.

Moreover, in the event of a failure of one or more of the functionalcomponents of the pre-mounted subassembly of functional components, highrepair costs must be expected, since the pre-mounted subassembly offunctional components is located in the interior of the tank andconsequently must be dismantled entirely.

This shows that the pre-mounted subassemblies of functional componentsin the prior art allow only a limited design flexibility in thearrangement of the functional components on the tank.

With this as background, it is the object of the present invention todesign a tank for a motor vehicle operating fluid of the above-mentionedtype, which does not have the disadvantages known from the prior art,and in particular which allows the designer more flexibility in thestructural design of such a tank.

To achieve this object, the present invention proposes that theplurality of functional components of the tank be arranged on segmentsof the tank wall that are positioned at an incline with respect to eachother. In this manner it is possible to eliminate a separate functionalcomponent group which is pre-mounted to the tank wall and forms aportion thereof. Thus it is possible to arrange the functionalcomponents in a simple manner according to their physical operatingprinciples and usages, in differing orientations at mutually inclinedtank wall segments and thus to ensure the satisfactory function of eachindividual functional component. Consequently, the individual functionalcomponents are not restricted to being arranged in the limited region ofa pre-mounted group of functional components. Thus the functionalcomponents can be arranged at a greater distance from each other, sothat mutual interference among the individual functional components isreduced or can even be eliminated. Accordingly, the individualfunctional components can be arranged at any particular location on themutually inclined tank wall segments. A plurality of functionalcomponents will thus be arranged on the tank wall using the plurality ofattachment formations. By the additional use of even those tank wallsegments which are arranged at an incline to each other, the individualfunctional components can also be arranged at those points of the tankwall which are tailored to the installation space available in the motorvehicle and to the geometry of the tank. An individualized arrangementof the individual functional components allows a particularly efficientfunctioning of each of the individual functional components.

The functional components designed for pumping and/or for cleaningand/or for detecting a property and/or for changing a property of theoperating fluid can be selected from a group which comprises: A pressuresensor to detect the pressure in the tank, a fill-level sensor to detectthe fill level of operating fluid located in the tank, a temperaturesensor to detect the temperature of the operating fluid and/or thetemperature of the outside environment, a quality sensor to detect thequality of the operating fluid, a heating device for heating theoperating fluid, a pumping device for pumping the operating fluid, afilter device for filtering the operating fluid, and a sensor fordetecting cavities in the frozen operating fluid located in the interiorof the tank.

For example, if a capacitive fill-level sensor and a capacitive qualitysensor are provided on the tank wall, then the fill-level sensor will bepositioned orthogonal to and the quality sensor parallel to the surfaceof the operating fluid in the tank. According to the present invention,the mutual interference between the capacitive fill-level sensor and thecapacitive quality sensor can be easily eliminated in that the twosensors are arranged on mutually inclined, in particular mutuallyorthogonal segments of the tank wall.

Selection of a specific type of a particular functional component issubject to little or no restrictions, owing to the flexibility inpositioning of the functional components on the tank wall.

The fill-level sensor, for example, can be a capacitive fill-levelmeter, a fill-level meter using ultrasound, or even another method ofphysical metering can be used to detect the fill level.

A property of the operating fluid means, for example, such factors asthe temperature, the quality, represented, for example, by its chemicalcomposition and/or by a fraction of a substance contained therein, oralso the pressure and similar factors.

In the present invention, the concept of “tank wall” is understood tomean that the interior side of the tank wall is adjacent to the tankinterior space, and the outer side of the tank wall is adjacent to theoutside environment of the tank. Preferably both the interior and theexterior sides of the tank wall are designed as one solid wallstructure, without any hollow space located there between.

Usually the tank wall of a tank comprises a top wall, a bottom wallpositioned opposite to the top wall, and a side wall which connects thetop wall to the bottom wall. The mutually inclined tank wall segmentscan then be formed by the top wall, the bottom wall and the side wall.The functional components thus can also be arranged at the side wall,and not exclusively at the top and/or bottom wall, so that the availablesurface area of the tank wall can be used more efficiently.

Preferably a pumping device for pumping operating fluid, in particularform the outlet opening of the tank, is disposed on the tank wall as afunctional component. Preferably the pumping device is disposed at theouter side of the tank wall, so as not to reduce the volume of the tankavailable for the operating fluid present in the tank. The pumpingdevice features a suction side for intake of operating fluid and apressure side for outlet of operating fluid.

For example, the pumping device can be a gear-type pump, a membrane pumpor a hose pump, wherein little or no restrictions are imposed withrespect to the selection of the kind of pumping device, because it canbe placed anywhere on the tank wall.

It is an additional advantage if a filter device is disposed as onefunctional component at the tank wall for filtering of operating fluid,in order to clean the operating fluid of impurities. Preferably thefiltering device is arranged at the interior side of the tank wall, sothat it is flushed by the fluid being filtered, which allows aparticularly simple infeed of the operating fluid to the filter device.

According to one preferred embodiment, the infeed of operating fluid tothe pumping device takes place such that the filter device is connectedto the conveyor device using a first line extending into the interior ofthe tank for control of the operating fluid. The first line includes aninlet end nearer to the filter device, and an outlet end nearer to thepumping device, wherein the first line is connected by its outlet end tothe suction side of the pumping device. In this way the pumping devicereceives cleaned operating fluid, so that the pumping device isprotected against damage due to impurities in the operating fluid. Thefirst line can lead out of the tank and can thus pass through the tankwall, for example, when the conveyance device or another functionalcomponent cooperating with the first line is disposed on the outer sideof the tank wall.

Like a second line to be described below, the first line also includes aline wall which surrounds a line volume inside the tank interior and isseparate from the remaining tank interior volume. The first and thesecond lines can be designed as multi-part or as a single piece. Thefirst and the second lines can additionally include flexible segments,such as hoses, and/or rigid segments, such as connection tubes at thetank wall. In order to keep the assembly expense low, the connectiontubes are preferably designed as integral with the tank wall.

The pumping of operating fluid from the pumping device to the outletopening of the tank takes place preferably in that the pumping device isconnected to the outlet opening of the tank by a second line leadingfrom the tank for control of operating fluid. The second line featuresan inlet end nearer to the pumping device, and an outlet end nearer tothe outlet opening of the tank, wherein at least the outlet end of thesecond line leads out of the tank—and thus passes through the tank wall,for instance—and its inlet end is connected to the pressure side of thepumping device. In this manner a flow path sealed against the tankinterior is created for the pumping of cleaned operating fluid from thetank to the outlet opening, which prevents contamination of any alreadyfiltered operating fluid. A pressure sensor can be provided on thesecond line to detect the pressure of the operating fluid in the secondline connected to the pressure side of the pumping device. Preferablythis pressure sensor is disposed on the tank wall and thus is located ata segment of the second line leading from the tank.

If the pumping device is disposed at the outer side of the tank wall,then the second line can also lead out from the tank at its outlet end,thus passing through the tank wall. This can be an advantage when thereis insufficient space available for placement of a line leadingoperating fluid away from the pumping device in a region of the outsideperimeter of the tank. This method can also be an advantage when thesuction side and the pressure side of the pumping device are locatednear each other, in particular when they are located on the same side ofthe pumping device. Consequently, with the pumping device located at theouter side of the tank wall, the first line and the second line togetherlead from the tank for an odd number of times, at least three times.

The outlet opening of the tank can be located at any place on the tankwall. Consequently it is possible to position the outlet opening not atthe geodetically lowest point of the tank wall. But preferably the inletend of the first line, and thus preferably the filter device arearranged at the geodetically lowest point of the tank wall, so that theinlet end of the first line and/or the filter device (when the tank isat least partly filled) is always supplied with operating fluid.

If the filter device has a labyrinthine structure, then anti-sloshbaffles can reduce the sloshing noise of the operating fluid. Inaddition, the pressure of the operating fluid can be held constant dueto the integrated labyrinth effect, even at low fill levels.

The tank wall is preferably produced by using an injection moldingprocess. The injection molding process is a particularly versatilemethod which makes it possible to adapt the structure of the tank todifferent installation-space conditions in motor vehicles.

In the case of a tank produced by the injection molding method, the wallthickness of the tank wall can be produced thinner than for a tankproduced by a blow mold method. Preferably the wall thickness of thetank wall is between 3 mm and 3.5 mm. In this way both material andweight, and thus also costs, can be saved.

The tank wall can be produced from at least two tank shells, preferablyfrom exactly two tank shells, so that the assembly of functionalcomponents to be disposed on the tank wall will be simplified incomparison to a tank produced as a single part, due to improvedaccessibility. For reasons of improved maintenance of the tank, it ispreferable to arrange the plurality of functional components on onesingle tank shell. Preferably the plurality of functional components isdisposed on the lower (relative to the install position of the tank in ahorizontally standing motor vehicle) tank shell.

In addition, due to the manufacture of the tank using an injectionmolding process it is possible to equip the tank with one or with aplurality of integral anti-slosh baffles protruding into the interiorspace of the tank, so that a subsequent assembly of slosh baffles can beomitted. Anti-slosh baffle walls are used to reduce the slosh movementsof the operating fluid within the tank and to reduce any resultantsloshing noise.

Also, with regard to a tank produced by means of an injection moldingmethod, by a suitable selection of material for the tank it is possibleto produce a supporting component for the tank which is optimized withregard to material and weight, instead of a metal supporting componentwhich is normally used for the tank in the prior art.

The plurality of attachment formations integrated with the tank wall canbe produced preferably jointly and simultaneously with the tank wall byan injection molding process. The attachment formations designedintegrally with the tank wall can be, for example, contact surfaces forindividual functional components, elevations or depressions worked intothe tank wall, sealing surfaces or such. The attachment formationsdesigned integral with the tank wall can also include transit openingsfor individual functional components and/or their supply connectors forelectrical power which are also provided in the tank wall. In addition,the attachment formations designed integral with the tank wall can beconnector tubes which form segments of the first or of the second line,for example, to connect a flexible segment of the first or of the secondline to a pumping device arranged at the outer side of the tank wall.

When equipped with a heating apparatus, the tank can also perform itsfunction reliably even at low ambient temperatures, in particular atambient temperatures at or below the freezing point of the operatingfluid. It is possible that the heating apparatus will provide moreheating power to defined locations of the tank wall than at otherlocations.

The heating apparatus is preferably a flexible heating element which atleast partly covers the interior side of the bottom wall. The surface ofthe flexible heating element in contact with the operating fluid,however, is greater when the heating apparatus essentially completelycovers the bottom wall. If a flexible heating element with heating pathsdisposed between two plastic foils is used, then more heating power canbe generated at defined locations of the tank wall, so that the heatingpaths at the defined locations are placed more closely together than atother locations. Although a heating apparatus designed as flexibleheating element is preferred, it is still quite possible that theheating apparatus can have a rigid design.

If the filter device and the heating apparatus overlap on the segment ofthe tank wall which supports them, then in the event that the ambienttemperature falls to or below the freezing temperature of the operatingfluid, then the filter device can be protected against damage byactivation of the heating apparatus; such damage can be caused by partlyor entirely frozen operating fluid present in the interior of the tank.Due to the application of heat from the heating apparatus in the regionof the filter device, any frozen operating fluid present there can bemelted, or the formation of ice in the region of the filter device caneven be prevented. Thus the filter device can always supply a quantityof operating fluid to the conveyance device.

In comparison to a non-insulated tank, a thermal insulating device canreduce the heat loss to the environment, especially in the case when aheating apparatus is activated in the tank interior. Preferably at leastone thermal insulating device is arranged at the underside (relative tothe install position of the tank) which is most exposed to the outsideenvironment, that is, at the outer side of the bottom wall of the tank.In order to further reduce the heat loss from the tank, an air gap canbe provided, at least in sections, between the insulating device and theouter side of the bottom wall of the tank.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The present invention will be explained in greater detail below withreference to the attached drawings.

FIG. 1. shows a rough schematic, cross-sectional view of a motor vehicletank for operating fluid according to the invention, with functionalcomponents arranged on the tank wall.

In FIG. 1, the motor vehicle tank for operating fluid according to theinvention is depicted in a roughly schematic form and is designated bythe general reference number 10. The tank 10 is depicted in alongitudinal cross section.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The tank 10 comprises a tank wall 12 with an interior side 14 and anexterior side 16. The tank wall 12 comprises a tank interior space 18and has a fill opening 20 for filling of operating fluid into the tank10, and an outlet opening 22 for drainage of operating fluid from thetank 10. The tank wall 12 is formed from a top wall 24, a bottom wall 26located opposite the top wall 24, and a side wall 28 which connects thetop wall 24 with the bottom wall 26. The tank wall segments of the tankwall 12: Top wall 24, bottom wall 26 and side wall 28, form an outercasing of the tank 10. The interior side 14 of the tank wall 12 sealsagainst the tank interior 18 and the outer side 16 of the tank wallseals against the outside environment 30 of the tank 10.

Furthermore, in the depicted exemplary embodiment, the tank wall 12produced by an injection molding method features an upper tank shell 12b and a lower tank shell 12 a, which are securely joined together whenthe tank 10 is in the mounted state. The terms “upper” and “lower”pertain to the install position of the final mounted tank 10 in ahorizontally standing motor vehicle.

The functional components of the tank 10 on the interior side 14 of thebottom wall 26 are: a fill level sensor 32, a temperature sensor 34, apressure sensor 44 and a filter device 38. The interior side 14 of thebottom wall 26 is covered essentially entirely by a flexible heatingelement 40. The flexible heating element 40 and the filter device 38overlap on their supporting tank wall segment. In the illustratedexemplary embodiment the filter device 38 is attached by screws 42 tothe bottom wall, and each of the screws 42 has a self-cutting thread andis screwed into a blind hole formed in the bottom wall 26 and used asattachment formation. The pressure sensor 44 for example, can be used todetect the fill level of the operating fluid in the tank, using ahydrostatic measurement of fill level. The pressure sensor 44 can alsobe set up to detect a pressure increase in the tank 10 as an indicationof a possible plugging of any existing ventilation line, and thus as anindication of a pending loss of functionality.

As additional functional components of the tank 10, a quality sensor 36and a pump 46 as pumping device are arranged on the side wall 28. Thepumping device 46 is secured to the outer side 16 of the side wall 28 bymeans of a flange 48 and screws 50. Similar to the screws 42 of thefilter device 38, each of the screws 50 has a self-cutting thread whichis screwed into a blind hole formed in the side wall 28 and acting asattachment formations. The quality sensor 36 is arranged at the interiorside 14 of the side wall 28.

Each of the functional components: Fill level sensor 32, temperaturesensor 34, quality sensor 36, heating element 40, pressure sensor 44 andpumping device 46, is supplied with power via a connector 32′, 34′, 36′,40′, 44′ and 46′. In addition, contact surfaces are provided on the tankwall 12 as attachment formations for the fill level sensor 32 and forthe filter device 38. The heating element 40 is produced jointly andsimultaneously with the tank wall 12 in an injection molding process andis attached to the tank wall 12 with clips. The contact surfaces formedwith the tank wall 12 for the fill level sensor 32 and the filter device38, and also the clips for the heating element 40, are not depicted inFIG. 1. From FIG. 1 it is evident that all functional components arearranged in the lower tank shell 12 a. The upper tank shell 12 bfeatures anti-slosh baffle walls 52 protruding into the interior 18 ofthe tank; these baffles are produced simultaneously and jointly with thetank shell.

To insulate the tank 10 against the environment 30, the outer shell 16of the bottom wall 26 is provided with an insulation element 54. An airgap (not depicted in FIG. 1) can be provided between the outer side 16of the bottom wall 26 and the insulation element 54.

The pumping device 46 is connected via a first line 56 leading from thetank 10 to a filter device 38 in a fluid-mechanics method. The firstline 56 features an inlet end 56 a near the filter unit 38, and anoutlet end 56 b near the pumping device 46. At its outlet end 56 b thefirst line 56 leads out from the tank 10. The outlet end 56 b of thefirst line 56 is connected to the vacuum side of the pumping device 45.

Furthermore, the pumping device 46 is connected via a second line 58 tothe outlet opening 22 in the tank wall 12 in a fluid-mechanics method.Similar to the first line 56, the second line 58 also leads out of thetank 10 and features an inlet end 58 a near the conveyance device 38,and an outlet end 58 b near the outlet opening 22. Both the inlet end 58a and also the outlet end 58 b of the second line 58 lead out of thetank 10. The inlet end 58 a of the second line 58 is connected to thepressure side of the conveyance device 46. A pressure sensor 45 todetect the pressure in the second line 58 is disposed at the outlet end58 b of the second line 58 at the interior side 14 of the tank wall 12.

Both the first line 56 and also the second line 58 divide the tankinterior space 18 into a line volume and a residual tank volume. Thefirst line 56 and the second line 58 comprise connection tubes 57 b and59 a and 59 b, respectively.

The flow path of the operating fluid is as follows: Operating fluidfiltered in the filter device 38 flows into the inlet end 56 a of thefirst line 56 connected to the filter unit 38, and from there to theoutlet end 58 b of the first line 56 connected to the suction side ofthe conveyance device 46. The operating fluid pulled in by theconveyance device 46 is then pumped from the suction side to thepressure side of the conveyance device 46 and flows into the inlet end58 a of the second line 58. The conveyance device 46 pumps the operatingfluid to the outlet end 58 b of the second line 58 connected to theoutlet opening 22, and finally through the outlet opening 22 of the tank10.

The invention provides a motor vehicle tank for operating fluid, withfunctional components arranged thereon, wherein the functionalcomponents can be arranged on the tank with considerable designflexibility, in that the functional components are arranged on segmentsof the tank wall which are disposed at an incline to each other.

1. Tank for motor vehicle operating fluid for accommodating of a fluid,comprising: a tank wall forming an outermost casing of the tank, thetank wall having an inner side bordering a tank interior, and having anouter side bordering the external environment of the tank, a fillopening passing through the tank wall for inlet of the operating fluidinto the tank, an outlet opening passing through the tank wall foroutlet of the operating fluid from the tank, a plurality of functionalcomponents, wherein the functional components are designed for pumpingand/or for cleaning and/or for detecting a property and/or for changinga property of the operating fluid, and a plurality of attachmentformations designed as being integral with the tank wall for thepositioning of a plurality of functional components on the tank wall,wherein the plurality of functional components of the tank are disposedon segments of the tank wall which are disposed at an incline to eachother.
 2. The tank according to claim 1, wherein the tank wall comprisesa top wall, a bottom wall opposite to the top wall, and a side wallconnecting the top wall to the bottom wall, wherein the top wall, thebottom wall and the side wall form tank wall segments arranged at anincline to each other.
 3. The tank according to claim 1, wherein at thetank wall, preferably at the outer side of the tank wall, as onefunctional component a pumping device is arranged for pumping ofoperating fluid, wherein the pumping device features a suction side forthe intake of operating fluid and a pressure side for the ejection ofoperating fluid.
 4. The tank according to claim 1, wherein at the tankwall, as one functional component a filter device is arranged forfiltering of operating fluid.
 5. The tank according to claim 1, whereinthe filter device is connected to the pumping device by a first lineextending into the interior of the tank for guiding the operating fluid,wherein the first line features an inlet end nearer to the filterdevice, and an outlet end nearer to the pumping device, wherein thefirst line with its outlet end is connected to the suction side of thepumping device.
 6. The tank according to claim 5, wherein the pumpingdevice is connected to the outlet opening of the tank by means of asecond line for guiding operating fluid leading out of the tank, whereinthe second line features an inlet end nearer to the pumping devicenearer to the outlet opening of the tank, wherein the second line atleast at its outlet end leads out of the tank and its inlet end isconnected to the pressure side of the pumping device.
 7. The tankaccording to claim 1, wherein the outlet opening of the tank is notarranged at the geodetically lowest point of the tank wall.
 8. The tankaccording to claim 1, wherein the filter device has a labyrinthinestructure.
 9. The tank according to claim 1, wherein the tank wall isproduced by an injection molding process.
 10. The tank according toclaim 9, wherein the tank wall is formed from at least two tank shells.11. The tank according to claim 9, wherein at least one anti-sloshbaffle protruding into the tank interior are designed as beingintegrated with the tank wall.
 12. The tank according to claim 9,wherein the plurality of attachment formations designed integrally withthe tank wall are produced jointly and simultaneously with the tank wallin an injection molding process.
 13. The tank according claim 1, whereinat the tank wall, as a functional component a heating device is arrangedas a flexible heating element, which covers the inner side of the bottomwall at least partially, and most preferably covers it essentiallyentirely.
 14. The tank according to claim 13, wherein the filter deviceand the heating device overlap at the segment of the tank wallsupporting them.
 15. The tank according to claim 1, wherein aninsulating unit is arranged at the outer side of at least one of thetank wall segments.
 16. The tank according to claim 1, wherein theplurality of functional components is selected from a group whichcomprises: a pressure sensor to detect the pressure in the tank, afill-level sensor to detect the fill level of operating fluid located inthe tank a temperature sensor to detect the temperature of operatingfluid and/or the temperature of the outside environment, a qualitysensor to detect the quality of the operating fluid, a heating devicefor heating of the operating fluid, a pumping device for pumping of theoperating fluid, a filter device for filtering of the operating fluid,and a sensor for detecting of cavities in frozen operating fluid locatedin the interior of the tank.
 17. The tank according to claim 1, whereinat the inner side of the tank wall, as one functional component a filterdevice (38) is arranged for filtering of operating fluid.
 18. The tankaccording to claim 6, wherein the second line also at its inlet endleads out of the tank when there is a pumping device arranged on theouter side of the tank wall.
 19. The tank according to claim 7, whereinthe inlet end of the first line and/or the filter device is arranged atthe geodetically lowest point of the tank wall.
 20. The tank accordingto claim 9, wherein preferably the tank wall has a thickness of 3 mm to3.5 mm.
 21. The tank according to claim 1, wherein the tank wall isformed from exactly two tank shells.
 22. The tank according to claim 10,wherein the plurality of functional components is arranged on a singleone of the tank shells.
 23. The tank according claim 1, wherein at thetank wall, as a functional component a heating device is arranged as aflexible heating element, which covers essentially entirely the innerside of the bottom wall.
 24. The tank according to claim 1, wherein aninsulating unit is arranged at the outer side of at least one of thetank wall segments at least on the bottom wall.